July 05, 2019
6 min read
Save

New approach uses polypropylene suture for four-point scleral fixation of secondary IOL

A handshake maneuver is not required when using this technique.

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact customerservice@slackinc.com.

Visual rehabilitation in aphakia and malpositioned IOLs often requires surgical intervention with secondary IOL implantation. In addition, subluxated and dislocated IOLs may require repositioning or exchange. IOL exchange can be performed using various surgical approaches, including an anterior chamber IOL, iris-fixated IOL, sulcus-fixated IOL or scleral-fixated IOL. Scleral-fixated IOLs can be foldable or nonfoldable, using two-point or four-point fixation. Foldable lenses provide small entry wound size, and four-point fixation, unlike two-point fixation, decreases IOL tilt and increases IOL stability. Scleral fixation of secondary IOLs provides a near-normal anatomic seating of the lens, which reduces complications such as pigment dispersion, secondary glaucoma and potential optical aberrations including aniseikonia, lens edge glare and magnification.

Although use of 10-0 polypropylene (Prolene) suture for scleral fixation of secondary IOLs has a long track record, it has shown time-related suture degradation that can lead to IOL subluxation and dislocation. In the search for a better suture for scleral fixation of IOLs, surgeons have begun to use the increasingly popular polytetrafluoroethylene suture (Gore-Tex), which provides higher tensile strength and lower tendency for degradation. However, the manufacturer’s label warns against the use of this suture inside the eye. Hence, the intraocular use of Gore-Tex is prohibited by some hospitals and institutions in the United States to avoid potential medicolegal issues. Additionally, this suture is bulky and floppy and often requires a two-handed or a handshake technique for scleral fixation of IOLs.

We introduce the use of 8-0 polypropylene suture for four-point scleral fixation of a foldable acrylic posterior chamber IOL without the need for a handshake technique. To our knowledge, the surgical technique described here is the first use of 8-0 polypropylene suture for four-point fixation of a secondary foldable IOL without a handshake technique and was published in the Journal of Cataract and Refractive Surgery.

PAGE BREAK

Surgical technique

Conjunctival dissection is carried out to expose the bare sclera on the nasal and temporal sides corresponding to the trypan blue horizontal marks made on the peripheral cornea along a horizontal meridian that is centered over the visual axis (Figure 1a). Four sclerostomy sites are marked 2.5 mm from the limbus with a vertical separation of 4 mm (Figures 1b and 2a), that is, 2 mm superior and inferior to the horizontal marks. A corresponding 4-mm vertical lamellar scleral groove forming a suture bed is made using a 15° super blade on the temporal and nasal sides (Figure 1c). This groove will host the suture, avoid exposure and decrease potential infection risk. At 6 o’clock, a peripheral corneal incision permits the placement of a 20-gauge anterior chamber maintainer (Lewicky E4981, Storz Ophthalmic Instruments) (Figure 1d). A corneal entry wound is made with a super blade, and Viscoat (sodium hyaluronate 3%, chondroitin sulfate 4%, Alcon) is injected for endothelial protection. A 20-gauge 1.2-mm spearhead microvitreoretinal blade (Laseredge E7520, Bausch + Lomb) is used to perform the sclerostomies and is passed further until the tip is visualized via the pupil.

A 2.4-mm keratome blade is used to create a clear corneal incision at the 12 o’clock position, and Triesence (triamcinolone acetonide injectable suspension 40 mg/mL, Alcon) diluted 1:10 with sterile balanced solution, is injected to visualize the vitreous. If anterior vitrectomy is required, a biaxial 25-gauge anterior pars plana vitrectomy is carried out to clear the vitreous from the anterior chamber and pupillary area (Figures 1d and 2b). A four-haptic posterior chamber Akreos Advanced Optics aspheric IOL (Bausch + Lomb) is placed horizontally on the corneal surface, and two sets of 13-cm 8-0 polypropylene sutures are used to form two loops on either side. One suture is passed through the opening in the upper right haptic in an anterior-posterior direction (Figures 1e and 2c), followed by a posterior-anterior direction as it exits through the right lower haptic. This suture passage pattern is duplicated using the second suture on the left two haptics of the posterior chamber IOL (Figures 1f and 2c). The small inward protrusions within the openings of the right upper and lower haptics will help proper IOL orientation with the anterior IOL surface facing the surgeon.

Four-point scleral fixation of a posterior chamber IOL
Figure 1. Four-point scleral fixation of a posterior chamber IOL using an 8-0 polypropylene suture. Horizontal meridian and sclera are marked (a and b) followed by creation of a scleral groove for suture housing (c). A 20-gauge microvitreoretinal blade is used to perform four sclerotomies at the premarked scleral spots. Infusion is maintained via an anterior chamber maintainer, and anterior pars plana vitrectomy is performed through a sclerotomy site (d). An 8-0 polypropylene suture is passed anterior to posterior (e) in the first lower right haptic of the four-haptic IOL, followed by posterior to anterior as it exits via the right upper haptic opening, and this is repeated on the left side (f). The free ends of the sutures are passed through the corneal incision (g) and then out of the sclerotomy sites using 25-gauge forceps (h). The posterior chamber IOL is inserted behind the iris (i), and the sutures are pulled ab interno for optimum IOL centration. The sutures are tied (j), and the knots are embedded (k) and glued with fibrin glue. The corneal and conjunctival incisions are then sutured (l).

Source: Reprinted from Journal of Cataract and Refractive Surgery, 44(12), John T, Tighe S, Hashem O, Sheha H, New use of 8-0 polypropylene suture for four-point scleral fixation of secondary intraocular lenses, 1421-1425, 2018, with permission from Elsevier.

PAGE BREAK

The distal end of the first suture on the right side is introduced into the anterior chamber and positioned just behind the iris plane in the pupillary area. Unlike the polytetrafluoroethylene suture, the 8-0 polypropylene suture is rigid enough to stay in the resting position, and the surgeon does not have to hold the suture in a handshake maneuver. Twenty-five-gauge serrated forceps (Grieshaber Revolution DSP, Alcon) are passed ab interno through the distal sclerostomy site on the right side and used to grasp the tip of the stationary 8-0 polypropylene suture and pull it to the exterior ab interno (Figure 1g). Next, the proximal suture is passed in a similar way on the right side. On the left side, a similar suture passing technique is used beginning with the distal suture, thus resulting in all four 8-0 polypropylene sutures being externalized (Figures 1h and 2d). Thus, no handshake maneuver is required when using this technique.

key steps of four-point scleral fixation
Figure 2. The key steps of four-point scleral fixation of a posterior chamber IOL. After marking the sclerotomy sites (a), the scleral groove is made followed by pars plana vitrectomy through a sclerotomy (b). Passing the 8-0 polypropylene sutures through the haptics (c). Passing the free ends of the sutures through the corneal incision and then out of the corresponding sclerotomy sites (d). The sutures are pulled ab interno and tied for optimum IOL centration (e). The knots are embedded and the sclerotomies are glued, and then the corneal and conjunctival incisions are sutured (f).

The posterior chamber IOL is folded on its long axis and introduced into the posterior chamber via the corneal wound and through the pupil using Kelman-McPherson or similar forceps (Figure 1i). The two sets of sutures on the nasal and temporal sides are tightened, IOL centration is achieved, and the sutures are tied with the excess sutures cut and removed. The exposed 8-0 polypropylene suture is placed within the surgically created vertical scleral groove (Figures 1j to 1l and 2e). The suture knots are buried within the sclerostomy sites (Figure 1k). Fibrin glue is applied over the sclerostomy sites and the scleral groove. Conjunctiva is then approximated to the limbus and attached to the underlying sclera using fibrin glue (Figure 1l), supplemented by interrupted polyglactin (Vicryl) sutures (Figure 2f). The small-incision clear corneal wound is closed with interrupted 10-0 nylon sutures (Figure 1l).

Disclosures: The authors report no relevant financial disclosures.